1. Field of the Invention
The present invention relates to an electronic component, to a circuit board, to an electronic apparatus, and to a method for manufacturing an electronic component.
2. Description of Related Art
In recent years, an electronic component having a surface acoustic wave element (hereinafter, referred to as an “SAW element”) as a resonator or a band-pass filter or the like, has been used in electronic apparatuses, such as cellular phones or television receivers. Japanese Unexamined Patent Application, First Publications Nos. 2002-290184 and 2002-290200 disclose examples of the technique relating to an electronic component having an SAW element. Japanese Unexamined Patent Application, First Publication No. 2002-290184 discloses a technique relating to packaging of electronic components in which an SAW element and an integrated circuit that drives the SAW element are packaged into the same package. Another technique relating to packaging is disclosed in Japanese Unexamined Patent Application, First Publication No. 2002-290200, in which an SAW element is mounted on a first substrate and an integrated circuit is mounted on a second substrate.
Because of an increasing demand for reduction in the size of an electronic apparatus in which an electronic component having an SAW element is used, reduction in the size of electronic components also has been required. However, the technique disclosed in the above-described Japanese Unexamined Patent Application, First Publication No. 2002-290184 could not meet this demand for size reduction since an SAW element and an integrated circuit are arranged side by side. Likewise, the structure disclosed in Japanese Unexamined Patent Application, First Publication No. 2002-290200 have a difficulty in achieving reduction in the thickness (and/or size) since a first substrate on which an SAW element is mounted and a second substrate having an integrated circuit formed thereon are stacked together.
In addition to electronic components having SAW elements, size reduction of electronic components having other electronic elements, such as a crystal resonator, a piezoelectric vibrator, and a piezoelectric tuning fork, is also demanded.